Circular knitting machine needle selecting apparatus

ABSTRACT

Broadly, there is disclosed an improved apparatus and method for selecting controllably certain discrete bodies one from the other as the bodies move past a site of selection. More specifically, there is disclosed method and apparatus for selecting which of the needles carried within the tricks of the needle cylinders of rotary knitting machines are caused to knit or not to knit. In the device described, selection of the needles actually results, in the preferred arrangement, from the operation of magnet means including permanent and electromagnets upon edge portions of patterning or needle jacks located beneath the needles themselves, rather than by direct action upon the needles. The actuating or selecting mechanism generally comprises a first or lower magnet means that includes a pair of poles, one of which is shaped in such a fashion as to provide a cam surface against which one end (in this case, the lower end) of the jacks will be cammed into a preselected position. This preselected position is one in which the other ends of the jacks, here the upper ends, are moved into a select position where they can be magnetically engaged by a second or upper magnet means. The second magnet means includes a plurality of electromagnets, which in operation are sequentially energized, and permanent magnet means that serve to maintain the needle jacks in position for selection to the non-operative position and to maintain the jacks in the nonoperative (non-knitting) position for a length of time sufficient to permit the jacks to clear the knitting cams located circumferentially about the periphery of the needle cylinder.

[ 5] Dec. 3, 1974 1 CIRCULAR KNITTING MACHINE NEEDLE SELECTING APPARATUS[75}- Inventor: Ronald G. Wolfshagen, Fullerton,

Calif.

[73] Assignee: Rockwell International Corporation,

Pittsburgh, Pa.

22 Filed: Apr. 19, 1971 21 Appl. No.: 135,319'

52 US. Cl .Q. 66/50 R [51] Int. Cl D041) 15/78 [58] Field of Search66/50 R, 25, 75, 154 A, 66/50 A, 50 B [56] References Cited UNITEDSTATES PATENTS 3,262,285 7/1966 Beguin et a1...'. 66/50 R 3,283,54111/1966 Cerjat 1. 66/50 R 3,292,393 12/1966 Ribler 66/154 A X 3,449,9286/1969 Schmidt et al.-. 66/50 R 3,518,845 7/1970 Cerjat 66/50 R3,710,594 l/l973 Bourgeois 66/50 R FOREIGN PATENTS OR APPLICATIONS1,116,744 6/1968 Primary Examiner-Wm. Carter Reynolds I Attorney, Agent,or FirmFloyd S. Levison; Dennis OConnor; Richard A. Speer [57] ABSTRACTBroadly, there is disclosed an improved apparatus and Great Britain66/50 R method for selecting controllably certain discrete bodies onefrom the other as the bodies move past a site of selection. Morespecifically, there is disclosed method and apparatus for selectingwhich of the needles carried within the tricks of the needle cylindersof rotary knitting machines are caused to knit or not to knit. 1n thedevice described, selection of the needles actually results, in thepreferred arrangement, from the operation of magnet means includingpermanent and electromagnets upon edge portions of patterning or needlejacks located beneath the needles themselves, rather than by directaction upon the needles. The actuating or selecting mechanism generallycomprises a first or lower magnet means that includes a pair of poles,one of which is shaped in such a fashion as to provide a' cam surfaceagainst which one end (in this case, the lower end) of the, jacks willbe cammed into a preselected position. This preselected position is onein which the other ends of the jacks, here the upper ends, are movedinto a select position where they can be magnetically engaged by asecond or der.

12 Claims, 8 Drawing Figures I III mf Pmmngm m I SHEET 18? Pmmwn 319MSHEET 30F 4 PAIFNIE can 31974 SHEET U 0F 4 FIG. 7.

Indexing Secf/an Depress/0g Ac/uaf/ng Sec/ion Seal/on CIRCULAR KNITTINGMACHINE NEEDLE SELEIITING APPARATUS BACKGROUND OF THE INVENTION 1. Fieldof the Invention v i As briefly noted above, the present invention isconcerned with circular knitting machines generally known as the largediameter body type, but is not limited to that type of knitting machinesolely. Circular knitting machines basically comprise a cylindricalneedle cylinder which is mounted for rotation about a vertical axis. Theouter periphery of the needle cylinder is formed with a large number ofslots of generally rectangular cross-sectional configuration, commonlyreferred to as tricks, extending longitudinally generally parallel tothe cylinder axis. Within these slots or tricks are disposed a pluralityof knitting needles and usually one or more sets of needle jacks toaccomplish their various knitting functions. v

. Operation of then eedles or needle jacks, if they are to be thefunctioning means by which needles are caused to knit or not to knit, iscontrolled through appropriately located cams that at various times arein contact either with the needles or, in the present description, withthe needle jacks. The raise cams, i.e. those that cause the needles tomove vertically upwardly into the knit position are normally locatedjust adjacent the outer periphery of the needle cylinder so that buttsorother protrusions on the needle jacks can cooperate therewith. I

By and large, the only way in which knitpatterns heretofore could bychanged in existing equipment was to physically disassemble the variouscarn segments making up thecam rings and then reassemble themachine withan entirely different cam configuration to deliver the desired knitfabric. This procedure is obviously one that is time consuming, as wellas one resulting in excessive cost. The present invention eliminatesthis needless and costly interruption of service by providing a combinedpermanent and electromagnetic actuator assembly which can be controlledby suitable means'to automatically determine whether or not individualneedle jacks will be physically disposed to cause knitting or not. w

2. Description of Prior Art Although it was indicated above that mostknitting machines patterning changes have been on a puredisassemble-reassemble basis, some work has been done in the prior artto electromagnetically control patterning jacks for the purpose ofsimplifying needle selection procedures. For example, Beguin et al. U.S.Pat. No. 3,262,285 discloses an electromagnetic needle selection systemwhich utilizes electromagnets in a variety of ways to move jacks from anon-knitting to a knitting position upon energization of anelectromagnet. ln apparatus of this sort, however, the selectingmechanism is one of comparatively slow response time. Addi tionally, dueto the circumferential spacing which must exist between successiveneedle jacks and the fields to operate mechanical transducers. Themechanical transducers in turn cooperate with butts extending out fromthe lower ends of the patterning jacks. Here again, the fact thatmechanical linkage must exist between the element to be operated uponand the operating driver results in comparatively poor time responsewhich in turn necessitates slower operating speeds and decreasedproduction rates. I

The actuating mechanism of the present invention goes beyond thoseexisting in the prior artby virtue of providing for the first time asystem utilizing both permanent magnetic fields and electromagneticallygenerated fields to assure not only extremely quick response time butalso to produce surety in operation. It should be mentioned at thispoint that it would be possible to operate the present actuatingmechanism solely through the use of electromagnets but no constructivepurpose would be gained since permanent magnets can easily replace thefunction of certain of the electromagnets and thereby eliminate fieldcontrolling devices that would otherwise be necessary. Additionally, thepresent apparatus, because of its high rate of response can beeffectively controlled by electronically programmed apparatus to switchfrom one desired pattern to another with no down time for the alterationof patterning cams.

It is a principal object of this invention to provide an improved methodand apparatus for controllably selecting certain discrete bodies onefrom the other as the bodies move past a site of selection.

It is a further principal object of this invention to provide animproved apparatus and method for selectively effecting positioning ofpattern or needle jacks mounted wiithin the tricks of theneedle cylinderof a circular knitting machine to place the jacks in either a selectedor a non-selected position, as desired.

Another object of this invention is to provide an improved jack actuatorfor knitting machines, which'actuator includesm'eans for positioning thejacks in a normally operative condition unless acted upon by a differentpart of the actuator. v

Another object of thisinvention is to providean im proved jack actuatorfor use on a rotary knitting machine, which actuator includes meansforsubjecting the jacks to atranslating magnetic field such that anyselected jack can be subjected to the field independently of anyadjacent or adjoining jack. I

An additional object of this invention is to provide an improved jackactuator for use with rotary knitting machines which includes means forpositioning the jacks in a select position from which they canunerringly be caused to move to positions resulting in knitting ornonknitting, as desired.

A further object of this invention is to provide an improved jackactuator for use with rotary knitting machines which includes upper andlower magnet means for controllably effecting positioning andcorresponding ends of the jacks.

Other objects and advantages of this invention will be in part obviousand in part apparent by reference to the FIG. 3 is a front elevation ofa cam box illustrating the manner in which the jack actuator is locatedwith respect tothe jack raising cams;

FIG. 4 is a front elevation of the improved jack actuator of thisinvention;

FIG. 5 is a side elevation of the improved jack actuator of thisinvention;

FIG. 6 is a top plan view of the improved jack actuator with partsremoved to show the manner in which the magnets of the upper part of theactuator are disposed; and

FIG. 7 is a bottom view of a fragmentary portion of the structure ofFIG. 3 illustrating the manner in which the lower portion of the jackactuator effects positioning of the jacks.

FIG. 8 is a top elevation of the lower portion of the magnetic staticforce assembly showing the two lower magnetic poles.

Generally, the actuator apparatus of this invention is to be used inconjunction with rotary knitting machines and preferably with largediameter machines having a multiplicity of yarn feeds, for example, 48or more. Applicability of the principles and structures herein describedare, however, relevant also to the small diameter knitting machines ofthe type now widely used to produce hosiery. It further must beunderstood, as mentioned earlier, that the method of selection heredescribed might apply as well to a linear system where discrete bodiesare caused to travel past a site of selection. The invention will bedescribed specifically in conjunction with a particular type ofapparatus, viz., a knitting machine, but it will be appreciated that itsuse can well extend into other areas of technology and engineering.

The construction and operation of the actuator apparatus can best beunderstood by referring to the drawings and specifically to FIG. 1 ofthe drawings in which the actuator apparatus 10 is shown mountedadjacent the external wall of the needle cylinder 11 for cooperationtherewith. Mounted between needle cylinder 11 and actuator apparatus 10is apattern jack 12 which is of the rocking type having a fulcrumlocated approximately midway between its upper and lower ends. Locatedimmediately above jack 12 is an intermediate jack [3 and finally theactual needle 14 which performs the kntting operation is positionedimmediately above intermediate jack 13. Pattern jack 12, intermediatejack l3 and the knitting needle 14 are all mounted within a slot ortrick present in the outer periphery of needle cylinder 11. The entireouter periphery of the cylinder is slotted to provide a series of thetricks which extend substantially parallel to the axis of rotation ofthe knitting cylinder (not shown).

The actuator apparatus 10 is mounted on the machine base that alsocarries the needle cylinder 1 1. Also shown in FIG. 1, immediatelybeneath the actuator apparatus and secured to the machine base is ajackraising cam 15 that is also shown in FIGS. 2 and 3 of the drawings.These jack-raising cams are mounted on the machine in segments referredto as cam boxes and are disposed completely around the needle drumcircumferentially, so that all jacks 12 during each full cylinderrotation may be acted upon by the raising cam 15 if this is desired.

Also shown in FIG. 1, immediately above the actuator apparatus andsecured to machine structure, is a jack lowering cam 16 that is alsoshown in FIGS. 2 and 3 of the drawing. These jack lowering cams aredisposed completely around the needle cylinder circumferentially, sothat the butts of all raised intermediate jacks 13 during each fullcylinder rotation are acted upon by the jack lowering cam. Theseintermediate jacks in turn bear upon the corresponding raised patternjacks 12 to return them to the lowered position for selection ornon-selection by the succeeding actuator apparatus. FIG. 1 also shows,adjacent to the needle 14 and secured to machine structure, a needle cam17. These needle cams are disposed completely around the needle cylindercircumferentially, so that the parts of all raised needles 14 are actedupon by the needle cam to lower them after they take yarn to form astitch, and to cause them to perform stitch formation action.

Having described the general environment in which the actuator apparatus10 operates, the construction of the actuator apparatus might best beseen by referring to FIGS. 4 and 5 of the drawings. The apparatus itselfis made up of two principal operating subassemblies.

One of these comprises a magnetic static force asembly means 20 which islocated adjacent the lower end of the actuator apparatus and whichincludes permanent magnet means 28 with upper pole 30 and lower polesthat exert a magnetic force against the lower ends of the pattern jacks12 as they travel past these magnetic elements. I

The upper part of the actuator apparatus 10 has been designated as amagnetic force translation assembly means and is indicated by thenumeral 21. The magnetic force translation asssembly means includes aplurality of electromagnets 22 each of which is less than the spacingbetween the leading edges of two adjacent jacks'in width at its poleextreme and arranged in two levels at predetermined intervals tosuccessively overlap each other at the pole extremities. Thisarrangement enables a very narrow and yet continuously effectivesequential magnetic field to be applied to the open end of any patternjack [2, as it progresses past the actuator apparatus, without adverselyeffecting its immediate neighboring jacks, and without reliance onfriction or other mechanical means to overcome the at- I traction of thestatic magnetic force assembly means 20. The magnetic force translationassembly2l also includes a jack indexing magnet 23 (FIG. 4) which are inthis case shown to be permanent magnets but which may, alternatively,also be in the event it should be desired. The function of this magnetis to so effect the position of the pattern jacks that they arein'readiness to be acted upon by the electromagnets 22 when desired.Further, following the electromagnets 22 is jack latching magnet 24which will maintain magnetic engagement with any jacks that have beenacted upon by the electromagnets and hold them in the selected ornonknitting position for the required length of time to ensure that thelower end of the pattern jack will avoid any contact with one of theraising cams 15.

The exact layout of the permanent jack indexing magnet 23 selectingelectromagnets 22 and jack latching magnet 24 is shown clearly in FIG. 6where the uppermost pole of each of the magnets is shown, theelectromagnets 22 having coils 25 mounted on the closed ends thereof.These coils are, of course, connected by means of wires 26 to suitablesources of regulated voltage. In operation these magnets 22 areenergized in sequence starting with the first uppermost magnet 22immediately adjacent the jack indexing magnet 23. After level, has beenenergized after this second electromagnet 22 has been energizedtemporarily it is deenergized a predetermined time after the third ofthe e lectromagnet 22, which is located on the upper level, has beenenergized. This third electromagnet 22 is deenergized at a predeterminedtime after the selected jack has progressed to a location where the jacklatching magnet 24 can maintain the magnetic engagement of the jack withupper magnet'means 21. By this method of raising and sequencedenergization, the fields created by the electromagnets in effect travelas a narrow continuous and non-interrupted energy front across the faceofthe'magnetic force translation assembly. Although the figures do notclearly indicate it, all of the magnets are of the usual U shapeconfiguration so that the upper set of pole faces represent the termi- Ihear when drawn toward the pole faces through the indexing action of thejack indexing magnet 23 and subsequently the upper ends of those jackswhich are held by theselective action of electromagnets 22 and theholding action of jack latching magnet 24. By contacting guard cam'27there is not subsequent wear or attrition of the pole surfaces ofthevarious magnets or the materialwithin which the magnets are mounted.Also as seen in FIG.'6-, the bearing surface 29 of cam 27 forms an arcwhich when in proper relationship with the needle cylinder isconcentric, with the cylinder. 1 Therefore, those jacks which are heldagainst surface 29 by sequential energization of electromagnets 22 andsubsequently held by jack latching magnet 24 are maintained in'a fixedpositional orientation within their respe'ctive tricks relative to theactuator apparatus while progressing past the actuator apparatus.

i Returning now to the-lower or first magnet means (magnetic staticforce assembly 20) this structure is made up of a first and second pole,the first pole being designated by the numeral 30 and the second andlower pole indicated by the numeral 31. The first pole 30 performs nofunction other than that of providing a magnetic attraction helping tohold the lower end of pattern jacks 12 coming into contact with themagnetic static force assembly. The second pole 31, it will be noted,

however, particularly by reference to FIGS. 3, 7 and 8, I has a camsurface 32 which is configured to cause the lower end of the jacks tomove inwardly toward the needle cylinder and a cam surface 37"which isconfigured to permit the lower end of the jacks to move outwardly fromthe needle cylinder if this is desired. This first cam surface 32results in the upper ends of every one of the jacks 12 moving to aposition of close proximity with upper magnet means 21 where they can bepulled against cam surface 29 by the attraction of jack indexing magnet23 and subsequently selected to notknit, if this is desired, throughinteraction with magnetic fieldsoriginated with electromagnets 22 andsubsequently following jack latching magnet 24.

The second cam surface 37 of .pole 31 permits the lower endsof the jacksnot selected by upper magnet means 21 and through interaction with thestatic magnet field of lower magnet means 20, to be displaced outwardlyalong the cam surface 37 to a position where the notched lower sectionof the .jacks 12 will engage and be acted upon by the raising-cam 15.This can be'stv be seen in FIG. 1 where the lower end of the jack 12 isshown in the displaced position it assumes when it is not returnedagainst surface 29 of guard cam 27 by en- .ergization of electromagnets27. As shown, the notched lower end of the jack 12 will contactandsubsequently follow the contour of raising cam 15, which will raisethe intermediate jack 13 and the knitting needle 14 finally intoposition to take yarn for knitting.

By referring to FIGS. 3 and 8 of the drawings, it can be seen that thelower pole 31 of the magnetic static force assembly'is constructed insuch a way that'the bottoms of pattern jacks 12 make contact with camsurface 32, depending upon whether or not they have been previously in aknit (raised) or a non-knit (lowered) position. Those jacks that havebeen in the lowered or non-knit position are designated by numeral 33and first contact surface 32 about midway of the lower pole 31. Thosejacks that have been in the raised or knit position are indicated bynumeral 34 and contact surface 32 of pole 31 at an earlier point.As'seen in FIG. 3, these jacks 34 are additionally in the process ofbeing lowered by contact with'intermediate jacks 13 which have buttscooperating with lowering cam 16. This embodiment is preferred topermit. a closer spacing of the jack actuator apparatus 10circumferentially about the periphery of the needle cylinder as it isclear that the jack lowering action could be accomplished before jackcontact with .cam surface 32. The region-from the point of contact ofjacks 34 with surface 32 to a location about midway of the lower pole 31might be called the jack depressing section. This language isfunctionally descriptive because as the jacks progress from thedepressing section towardthe mid section, or jack indexing section, thelower ends of the jacks are depressed inwardly toward the needlecylinder 11 and into the respective tricks in the cylinder. In thisorientation the stepped or notched-lower ends of all jacks 33 and 34 arelocated outside of a planewhere they can come into contact with jackraising cams15.Such inward movement of the lower end obviously resultsin outward movement of. the upper ends of jacks 12 to bring them inclose proximity with the guard cam 27 of the upper magnetic means 21(magnetic translation force assembly); When this movement has beenachieved and any one jack is located in the jack indexing section,theupper ends of jacks 12 will be acted upon by the indexing magnet 23of upper magnet means 21 which partially neutralize the effect of thetween any jack 12, located circumferentially within the indexing sectionjack and the cam surface 29 provided that the jack 12 is an infinitelyrigid element. However, any real jack element is'not infinitely rigidand when loaded by forces acting at right angles to the longitudinaldimension at known distances on each side of a center support the jackwill deflect in a known manner within its elastic limit and dependingupon its cross section geometry. Similarly, any jack 12 locatedcircumferentially within the jack indexing section with its lower endheld against cam surface 32 by interaction with the magnetic field oflower magnet means 20, its mid-length located fulcrum point bearing onpivot cam 40, and its upper end interacting with the magnetic field ofjack indexing magnet 23 of upper magnet means 21 will elastically and ina predetermined manner deflect outwardly toward the pole ends of jackindexing magnet 23 until contact is made with surface 29 of guard cam27. Further, the elastic properties of a jack 12 are predetermined suchthat jack contact with all three cam surfaces 32, 40 and 29 will occursimultaneously in the jack indexing section of the actuator for each andevery jack in a full cylinder revolution irrespective of normal wear,obtainable part tolerances and uneven temperature expansions which wouldotherwise cause the dimension air gap relationship between the jack andthe magnets to be indeterminant. This condition is necessary for errorfree selection because first, clearance (air gaps) to the magnet meansand 21 are now the same for each and every jack at the select position,and second because with the jack bearing on the pivot cam surface 40there is no possibility that jack impact with this surface, throughcooperation with cam surface 37 on pole 31, can occur, such impactcausing undesired bounce or recoil of the jack away from the actuatorapparatus. Such acondition would result in selection errors at high jackcircumferential speeds. This action of positioning the jacks 12 in aselect positionthen permits energization of the electromagnets 22 toprovide the additional force that determines whether or not the upperend of the jack will be magnetically held against the guard cam 27 inopposition to the magnetic force of lower magnet means 20 acting on thelower endof the jack. v

Those jacks that are selectively held against guard cam 27 anddesignated bynumeral 35 in FIG. 8. Should the electromagnet 22 besequentially energized, the upper ends of the jacks 35 will be held tobear against the guard cam 27 as the jack is translated past theactuator apparatus by rotation'of the needle cylinder 11. The lower endsof jacks 35 are thereby maintained in a position where notched portionat the lower end of the jacks will avoid contact with raising cam 15.This can best be seen in FIG. 2 where the lower end of jack 12 is shownin the position it assumes when it is held by electromagnets 22 to clearraise cam 15. The result is then that the pattern jack merely passesbehind the raising cam rather than following the contour of the camwhich would raise the intermediate jack l3 and the knitting needle 14finally into position to take yarn for knitting.

If the electromagnets 22 are not energized, then the lower end of anypattern jack 12 will continue to be held by the lower magnets 30 and 31so that it will follow the contour of pole cam surface 32 on the polecam surface 37 into what is called the jack actuation section (see FIG.8). This is referred to as the jack actuation magnetic attraction oflower magnet means 20 to move awsay from the cylinder and out of itstrick to a position where it will engage and be acted upon by theraising cam 15. Jacks so disposed are identified by numeral 36 in FIG.8. Such outward movement of the lower end obviously results in inwardmovement of the upper end, the jack 26 pivoting about its fulcrum pointwhich is bearing on pivot cam 40, thereby increasing the displacementbetween the upper end of jacks 36 and the upper magnet means 21.Conversely, those jacks 35 which are acted upon by electromagnets 22progress along cam surface 29 into close proximity with the jacklatching magnet 24 which ensures that those selected jacks will havetheir lower ends held out of the plane where they can make any contactwith raising cams 15 again as shown in FIG. 8.

In operation, pattern jacks 12 are vertically mounted in thelongitudinally extending tricks of the needle cylinder 11 and rotate ina path on the periphery of this cylinder. At each yarn feeding stationaround the periphery of needle cylinder 11 there is located one of theactuator apparatus 10 so that at that location any needle can be causedto knit or not to knit depending upon whether or not the electromagnets22 are sequentially energized. The purpose for providing a multiplicityof electromagnets to effect the selection, when desired, of certain ofthe pattern jacks l2'is because of the desirability of providing as manyneedles in the needle cylinder as possible and to rotate the needlecylinder at an angular rate which is not limited by the selection vmeans. Obviously, to do this the lateral dimensions of each needle mustbe kept to an absolute minimum and when doing this, it then becomesnecessary that a very narrow and yet continuously effective magneticfield must be maintained to ensure that any one of the jacks are heldlong enough to remove them from the infue nc'e of the lower magneticmeans 20 into a selected position of non-knitting. Also, it is necessarythat the lower magnet means 20 must hold jacks 36 in contact with'camsurface 27 long enough to pivot their lower ends into a position wherethey will engage and be acted upon by raising cam 15. Because themagnetic force acting on the jack is directly, relatable to the edge orthickness dimension of the 7 jack, a practical force limit exists. Also,because the force required to displace the jack against its inertiabecomes increasingly great as the time available to displace the jackbecomes less, it follows that, for high angular cylinder speeds,

the amount of. jack displacement which can be practically accomplishedwithin a time period equivalent to one jack spacing may be inadequate tofully displacethe notched lower end of the jack 36 from the positionwhere it will avoid contact with the raising cam 15 to the positionwhereit will engage and cooperate with the raising cam. This condition isaccommodated by accomplishing jack displacement, over a time periodequivalent to multiplicity of jack spacings, which in turn determinesthe need for,the plurality of sequentially energized electromagnets 22to ensure that the individual selected jacks 35 are held long enough toremove their lower ends from the influence of the lower magnet means 20.When the drum is rotated so that the needles turn past each of thevarious selection stations, the bottom ends of the pattern jacks firstcome into contact with either the jack depressing or jack indexingsection of the lower pole 31 of the magnetic static force assembly. Atthis time the jacks with the cooperation of jack indexing magnet 23 areis a select position with the notched lower ends of the jacks retractedinto their cylinder tricks and located outside of a plane where they cancome into contact with jack raising cams 15. Here if the electromagnets22 remain unenergized, the jack will pivot about its fulcrum pointbearing on pivot cam 40 the lower end of the pattern jack in cooperationwith lower magnet means 20 will followalong the contour of cam surface37 of lower pole 31 and move outward from the needle cylinder to theposition where it will be acted upon by the next following raise cam 15.This of course vertically shifts all of the associated elements 12, 13and 14 upwardly and will cause the needle to take yarn and then tosubsequently draw down a new stitch. On the other hand, if the first ofthe electromagnets 22, and by first is meant the first one that isapproached by any given traveling pattern jack, is energized, it willact to hold the upper end of .the selected jack 12 against the guard cam27. With the upper end of jack 12 held against guard cam 27, the bottomend of the jack is maintained within its cylinder trick corresponding tothe position shown in FIG. 20f the drawings where it is located in aplane where it will completely pass the raise cam 15. Therefore noresultant upward movement of jack l2 and effected parts will take place.The permanent magnet jack latching magnet 24 will then take over afterall of the electromagnets 22 have been energized in sequence andmaintain the grip on the upper end ofjack 12 to assure that the lowerend of the jack will pass by the jack raising cam. Thus it can be saidin this arrangement that the jack indexing magnet 23 is locatedrotationally ahead of the permanent electromagnets 22 and that the jacklatching magnet 24 is located rotationally behind the elecous that therehas been provided an improved and radi- I cally different type ofapparatus which is capableof selecting discrete articles of very smalllateral dimensions with minimum probability of selecting or adverselyeffecting any of the other individual articles immediately adjoining oradjacent the article to be selected. In this case when knitting with. arotary knittingmaChine the selection must be certain and accurate at alltimes and fr the first time, this mechanism provides a magnetic meansformaking accurate selection of pattern jacks at high rotationalcylinder speeds.

Although the present invention has been described in connection withpreferred embodiments, it is to be understood'that modifications andvariations may be resorted to without departing from the spirit andscope of the invention as those skilled in the art will readilyunderstand..Such modifications and variations are considered to bewithin the purview and scope of the invention and the appended claims.

I claim:

1. Actuator apparatus for selectively effecting positioningof needlejacks mounted within the tricks of the needle cylinder of a circularknitting machine to place the jacks in either a selected or anon-selected position,

as desired, said apparatus comprising a magnetic static magnetic forcetranslation assembly means including a plurality of electromagnetsphysically arranged in a predetermined mannerto enable them selectivelyto magnetically engage the other end of each selected jack withsequentially applied magnetic fields overcoming said magnetic means ofsaid static force assembly means to hold the selected jack in theselected position where the associated needle will be caused to knit.

2. An apparatus as defined in claim 1 in which a pivot cam is locatedbetween said magnetic static force assembly and said magnetic forcetranslation assembly means to provide a fulcrum about which the jackswill pivot when acted upon by said magnetic static force assembly means.2

3. An apparatus as defined-in claim 1 wherein said magnetic meanscomprises a cam pole having a surface adapted to be contacted by saidone end of each jack,

said contact surface being configured to cause the jacks to move into aposition where they can be selected by said magnetic force translationassembly means when desired. I

4. An apparatus as defined inclaim 1 in which a pivot cam is locatedbetween said magnetic static force assembly and said magnetic forcetranslation assembly means to provide a fulcrum about which each jackwill pivot when acted upon by said magnetic static force assembly meansand in which said magnetic means comprises a pair of poles positioned tomagnetically engage said one end of each jack, at least one of saidpoles being configured to cause each jackto move into a position whereit can be selected by said magnetic force magnetically engage said oneend of each jack, at least one ofsaid poles being configured to causethe jacks to move into a position where they can be selected by saidmagnetic force translation assembly means when desired. l

6. An apparatus as defined in claim 1 wherein said plurality ofelectromagnets are physically arranged in a'manner such that theeffective fields thereof overlap fora predetermined length of time whensaidelectromagnets are sequentially applied, 'said length of time beingsuch as to enable maintenance of magnetic engagement with any selectedjack throughthe amount of arcuatetravel about the axis of rotation ofthe needle cylinder required to hold the selected jack in theinoperative'position andto enable the jack next following the selectedjack to be acted upon by said electromagnets independently.

7. An apparatus as defined in claim 6 wherein at least threeelectromagnets are present in said magnetic force translatingassemblymeans.

8. An apparatus as defined in claim 1 wherein said magnetic forcetranslation assembly includes jack -in dexing magnet means locatedrotationally ahead of said plurality of electromagnets to cooperate withsaid magnetic static force assembly means in positioning the jacks in aselect position where they can be magnetically engaged by said pluralityof electromagnets when they are energized.

9. An apparatus as defined in claim 8 wherein said jack indexing magnetmeans is a permanent magnet.

10. An apparatus as defined in claim 1 wherein said magnetic forcetranslation assembly means includes jack latching magnet means locatedrotationally behind said plurality of electromagnets to magneticallyengage said other ends of those jacks magnetically engaged by saidplurality of electromagnets and hold the jacks in the non-operativeposition for a predetermined period.

11. An apparatus as defined in claim wherein said jack latching magnetmeans is a permanent magnet.

12. Apparatus for selectively effecting movement of pattern jacksmounted within the tricks of the needle cylinder of a rotary knittingmachine to place the jacks in either an operative or a non-operativeposition, as desired, and said apparatus comprising:

a. first magnet means for magnetically engaging the lower ends of saidjacks to place the jacks in the operative position in which the needlescarried in the needle cylinder will becaused to knit, said first magnetmeans including: i l. a first pole, and

2. a second pole having a cam surface configured to cause the jacks tomove to a position of selection;

b. second magnet means for magnetically engaging the upper ends of saidjacks to move them into a non-operative position in which the needlescarried in the needle cylinder will be caused not toknit,

2. a permanent magnet located rotatably ahead of said plurality ofelectromagnets to cooperate with said first magnet means in positioningthe jacks in a select position where they can be magnetically engaged bysaid plurality of electromagnets when they are energized, and

3. a permanent magnet located rotatably behind said plurality ofelectromagnets to magnetically engage the upper ends of those jacksmagnetically engaged by said plurality of electromagnets and hold thejacks in a non-operative position for a predetermined period; and

c. a pivot cam located between said upper and lower magnet means toprovide a fulcrum about which the jacks will pivot when acted upon bysaid magnet means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO.3,851,500 DATED December 3, 1974 INVENTOR(S) :Ronald G. Wolfshagen It iscertified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

Column 1, Line 62 "eror" should be --error--.

Column 4, Line 47 following "be" first occurrence insert --anelectromagnet--.

Column 9, Line 45 "fr" should. be --for--.

Signed and Scaled this Fourth Day Of January 1977 [SEAL] Attest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner uflarentsand Trademarks

1. Actuator apparatus for selectively effecting positioning of needlejacks mounted within the tricks of the needle cylinder of a circularknitting machine to place the jacks in either a selected or anon-selected position, as desired, said apparatus comprising a magneticstatic force assembly including cam means adapted for physicalengagement with one end of each of the jacks to place the jack in theselected position in which the each associated needle carried in theneedle cylinder will be caused not to knit, magnetic means for holdingsaid one end of each jack in contact with said cam means, and magneticforce translation assembly means including a plurality of electromagnetsphysically arranged in a predetermined manner to enable them selectivelyto magnetically engage the other end of each selected jack withsequentially applied magnetic fields overcoming said magnetic means ofsaid static force assembly means to hold the selected jack in theselected position where the associated needle will be caused to knit. 2.a permanent magnet located rotatably ahead of said plurality ofelectromagnets to cooperate with said first magnet means in positioningthe jacks in a select position where they can be magnetically engaged bysaid plurality of electromagnets when they are energized, and
 2. Anapparatus as defined in claim 1 in which a pivot cam is located betweensaid magnetic static force assembly and said magnetic force translationassembly means to provide a fulcrum about which the jacks will pivotwhen acted upon by said magnetic static force assembly means.
 2. asecond pole having a cam surface configured to cause the jacks to moveto a position of selection; b. second magnet means for magneticallyengaging the upper ends of said jacks to move them into a non-operativeposition in which the needles carried in the needle cylinder will becaused not to knit, said second magnet means including:
 3. a permanentmagnet located rotatably behind said plurality of electromagnets tomagnetically engage the upper ends of those jacks magnetically engagedby said plurality of electromagnets and hold the jacks in anon-operative position for a predetermined period; and c. a pivot camlocated between said upper and lower magnet means to provide a fulcrumabout which the jacks will pivot when acted upon by said magnet means.3. An apparatus as defined in claim 1 wherein said magnetic meanscomprises a cam pole having a surface adapted to be contacted by saidone end of each jack, said contact surface being configured to cause thejacks to move into a position where they can be selected by saidmagnetic force translation assembly means when desired.
 4. An apparatusas defined in claim 1 in which a pivot cam is located between saidmagnetic static force assembly and said magnetic force translationassembly means to provide a fulcrum about which each jack will pivotwhen acted upon by said magnetic static force assembly means and inwhich said magnetic means comprises a pair of poles positioned tomagnetically engage said one end of each jack, at least one of saidpoles being configured to cause each jack to move into a position whereit can be selected by said magnetic force translation assembly meanswhen desired.
 5. An apparatus as defined in claim 1 wherein saidmagnetic means comprises a pair of poles positioned to magneticallyengage said one end of each jack, at least one of said poles beingconfigured to cause the jacks to move into a position where they can beselected by said magnetic force translation assembly means when desired.6. An apparatus as defined in claim 1 wherein said plurality ofelectromagnets are physically arranged in a manner such that theeffective fields thereof overlap for a predetermined length of time whensaid electromagnets are sequentially applied, said length of time beingsuch as to enable maintenance of magnetic engagement with any selectedjack through the amount of arcuate travel about the axis of rotation ofthe needle cylinder required to hold the selected jack in theinoperative position and to enabLe the jack next following the selectedjack to be acted upon by said electromagnets independently.
 7. Anapparatus as defined in claim 6 wherein at least three electromagnetsare present in said magnetic force translating assembly means.
 8. Anapparatus as defined in claim 1 wherein said magnetic force translationassembly includes jack indexing magnet means located rotationally aheadof said plurality of electromagnets to cooperate with said magneticstatic force assembly means in positioning the jacks in a selectposition where they can be magnetically engaged by said plurality ofelectromagnets when they are energized.
 9. An apparatus as defined inclaim 8 wherein said jack indexing magnet means is a permanent magnet.10. An apparatus as defined in claim 1 wherein said magnetic forcetranslation assembly means includes jack latching magnet means locatedrotationally behind said plurality of electromagnets to magneticallyengage said other ends of those jacks magnetically engaged by saidplurality of electromagnets and hold the jacks in the non-operativeposition for a predetermined period.
 11. An apparatus as defined inclaim 10 wherein said jack latching magnet means is a permanent magnet.12. Apparatus for selectively effecting movement of pattern jacksmounted within the tricks of the needle cylinder of a rotary knittingmachine to place the jacks in either an operative or a non-operativeposition, as desired, and said apparatus comprising: a. first magnetmeans for magnetically engaging the lower ends of said jacks to placethe jacks in the operative position in which the needles carried in theneedle cylinder will be caused to knit, said first magnet meansincluding: